Characterization of an extinct seabird colony on the island of Santa Luzia (Cabo Verde) and its potential for future recolonizations

Abstract

Islands worldwide have suffered seabird extinctions after the arrival of humans and the alien species they introduced. On Santa Luzia (Cabo Verde), an uninhabited island of 35 km 2 , the presence of an impressive quantity of petrel bones in coastal dunes suggested the previous existence of an important seabird colony. Yet, these remains had not been identified and no seabird extinctions have been reported for the island. This paper characterizes the extinct seabird colony of Santa Luzia and discusses the chronology and possible causes of its demise. A total of 130 grid points in a 5 km 2 area and 38 supplementary points within and outside the main study area were excavated to collect bone remains. A total of 1318 anatomical elements, identified as White-faced Storm Petrel Pelagodroma marina eadesorum (85.3% of the minimum number of individuals, MNI), Boyd's Shearwater Puffinus lherminieri boydi (11.8% MNI) and Cape Verde Storm Petrel Hydrobates jabejabe (2.9% MNI), were found in 18% of the sampling points, within 1.25 km 2 . Neither of the two former species currently breeds on Santa Luzia. In addition, two bones of the Cape Verde Shearwater Calonectris edwardsii and Pterodroma sp. were detected in the supplementary points. Radiocarbon dating of White-faced Storm Petrel (n = 10) and Boyd's Shearwater bones (n = 13) suggests that the colony probably went extinct during the first half of the twentieth century. The recent extinction of these species on Santa Luzia might be consequent on the arrival of humans and their domestic animals on the island. We estimate that the extinct seabird populations must have been at least hundreds of thousand strong, far larger than current populations of the same species in Cabo Verde. We suggest that, following feral cat eradication, Santa Luzia has a significant potential for seabird restoration. KeywordsBones • Fossils • Radiocarbon • Petrel • Cape Verde • Extinction Zusammenfassung Beschreibung einer erloschenen Seevogelkolonie auf der Insel Santa Luzia (Kap Verde) und deren Potenzial für zukünftige Wiederansiedlungen Weltweit kam es auf Inseln nach der Ankunft des Menschen und den durch diesen eingeführten fremden Arten zum Aussterben von Seevögeln. Auf Santa Luzia (Kap Verde), einer 35 km 2 großen unbewohnten Insel, deutet das Vorhandensein einer beeindruckenden Menge an Sturmvogelknochen in den Küstendünen auf die ehemalige Existenz einer bedeutenden Seevogelkolonie hin. Bislang waren diese Funde aber noch unbestimmt, und es waren keine Aussterbeereignisse von Seevögeln von dieser Insel bekannt. In diesem Beitrag beschreiben wir die erloschene Seevogelkolonie auf Santa Luzia und diskutieren Chronologie und mögliche Ursachen ihres Verschwindens. An insgesamt 130 Rasterpunkten in einem 5 Communicated by C. Barbraud.

Density and ecological drivers of free‐ranging cat abundance and activity in Madeira Island, Macaronesia

“…Similar findings have been reported in numerous other studies (e.g., Hervías et al, 2014), and likely explain the restricted breeding range of Manx shearwater in Madeira. Notwithstanding that multiple additional factors (e.g., habitat loss due to fires and light pollution; Dias et al, 2019) are likely impacting seabirds in Madeira, evidence from the Canary Islands, where cats are suspected to have contributed to the post‐European arrival extinction of the Lava shearwater Puffinus olsoni (McMinn et al, 1990; Rando & Alcover, 2008), and from Cape Verde, where they were implicated in the island‐level extirpation of Boyd's shearwater Puffinus lherminieri boydi from Santa Luzia (Alho et al, 2022), suggests that if left unchecked the free‐ranging cats—currently particularly abundant/active near the breeding grounds of the Ecological Park of Funchal colony of Manx shearwater (Figure 3)—might compromise the long‐term persistence of the species in Madeira.…”

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Trust your guts? The effect of gut section on diet composition and impact of Mus musculus on islands using metabarcoding

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Environmental coastal research: a systematic review for Azores and Cabo Verde, two peripherical Macaronesian archipelagos

“…The islands of Santa Luzia (Cabo Verde) and Corvo (Azores), exhibit percentages of 100%, as the entire territory of these areas are PAs. The small Corvo community is highly dependent on marine resources and with a tangible cultural heritage associated with the sea (Calado et al, 2011a), and Santa Luzia in Cabo Verde is an uninhabited island (Alho et al, 2022) only temporarily occupied and used by a small fishermen community (Deniz and Matos, 1994). A significant percentage of PAs can be represented by seamounts and islets.…”